Housing violations in NYC: which agency does what.

The agencies: the flow, HPD, DOB, OATH/ECB, 311

See what is open on one building.

The flow, in order

Most housing violations in NYC start the same way. A tenant calls 311. The call itself is a request for the city to look at something, not a finding of anything. It is answered by whichever agency actually handles that kind of complaint, and most 311 volume is not housing-related at all.

1. HPD, the Department of Housing Preservation and Development, schedules an inspection once a housing complaint reaches it. Only if an inspector confirms a Housing Maintenance Code condition does HPD issue a violation and mail the owner a Notice of Violation.
2. From that point the violation is public: searchable on HPD Online, and in the data this site reads. The owner is expected to correct the condition and certify the correction with HPD.
3. Separately, and often on the same building, DOB, the Department of Buildings, governs the physical work: permits, plan approval, elevators, boilers, cranes, and whether construction underway matches what was filed. DOB's own inspectors and plan examiners can issue a violation directly, with no 311 call involved at all.
4. When DOB, or another city agency, wants to prosecute a violation it has issued, the matter goes to a hearing. That hearing is OATH, sitting as ECB. It is where whoever the notice names can contest it, and where a judge decides the case.

If the certify-by date on an HPD violation passes with nothing filed, the status moves to Not Complied With, tracked with every other status in the status glossary.

What OATH/ECB is not

The single most common mix-up in this category is treating OATH/ECB as a third enforcement agency alongside HPD and DOB. It is not. OATH, the Office of Administrative Trials and Hearings, does not send inspectors and does not decide what counts as a violation. Sitting as ECB, the Environmental Control Board, it is the venue: the room where the agency that already wrote the notice has to prove it, and where a penalty gets set once the hearing concludes. The full explanation, with every hearing outcome, is on its own page.

A building can carry no OATH/ECB history at all and still have an open HPD violation. A building can also carry an OATH/ECB judgment with no HPD violation at all, because the matter that reached the hearing came from DOB, not HPD. The two facts are independent, and reading only one of them is reading part of the file.

What we hold from each source

HPD and 311 rows are our full copy of each city dataset. The DOB row is the city's DOB ECB Violations dataset: DOB's own violations heard at OATH, not every agency OATH hears.

Where HPD and DOB actually overlap

Right now, 98,191 properties have an open HPD violation and 32,840 have an active OATH/ECB matter. 12,307 properties have both at once: 12.5% of the open-HPD group, and 37.5% of the active-OATH/ECB group. Widen the window to everything in our copy, not only what is open today, and 158,420 properties have had an HPD violation, 55,377 have had a DOB matter, and 24,781 have had both, 15.6%.

Counted by BBL, the city's own parcel identifier, never by owner or building name. A property counts once per row regardless of how many violations it carries.

311, and why a complaint is not a violation

311 sits upstream of everything above. Calling 311 opens a service request; on its own, it does not create a violation. Our own copy of 311 holds every agency's service requests, not only housing ones, so most of that volume is never headed to HPD at all. Only 25.8% of the 460,596 properties with a 311 request in our trailing window also have an HPD violation. The full breakdown, including the reverse direction, is on its own page.

Why the distinction pays off

A building can look clean at HPD and still carry a real penalty from an OATH/ECB judgment that started with a DOB notice, such as work without a permit or a sidewalk shed out of code, and never touched the housing code at all. The three answer different questions. HPD tracks conditions inside occupied units. DOB tracks the physical building and the work being done to it. OATH/ECB decides whether an agency's notice holds up once whoever it names has had the chance to contest it. Checking only one of the three is checking a third of the file.

No building or owner is named on this page. Source: NYC Open Data, the city's own published datasets. How to check your own building, status codes decoded, violations by borough, citywide, ViolationScout.